INTRODUCTION: Few reports exist regarding the therapeutic effects of probiotics on chronic constipation in elderly individuals. This study evaluated the effects of Bifidobacterium longum BB536 in elderly individuals with chronic constipation. METHODS: This was a randomized, double-blind placebo-controlled, parallel-group superiority trial in Japan (UMIN 000033031). Eighty older adults diagnosed with chronic constipation were randomly assigned (1:1) to receive either probiotics (B. longum BB536, 5 × 10¹⁰ colony-forming unit, n = 39) or placebo (n = 41) once daily for up to 4 weeks. The severity of constipation was evaluated using the Constipation Scoring System. The primary end point was the difference in the changes from baseline in the constipation scoring system total score between the 2 groups at week 4. RESULTS: A total of 79 patients (mean age of 77.9 years), including 38 patients in the BB536 group and 41 in the placebo group, completed the study. The primary end point was not significant (P = 0.074), although there was significant improvement (P < 0.01) in the BB536 group from baseline to week 4, but there were no significant changes in the placebo group. There was a significant difference and a tendency toward a difference in the changes from baseline on the stool frequency (P = 0.008) and failure of evacuation (P = 0.051) subscales, respectively, at week 4 between the 2 groups. Few adverse events related to the probiotics were observed. DISCUSSION: The primary end points were not significant. However, probiotic supplementation significantly improved bowel movements. These results suggest that B. longum BB536 supplementation is safe and partially effective for improving chronic constipation in elderly individuals.

A recent meta-analysis found that probiotics have moderate-to-large beneficial effects on depressive symptoms in patients with psychiatric disorders. However, it remains unclear how the baseline gut microbiota before probiotic administration influences the host’s response to probiotics. Therefore, we aimed to determine whether the predicted functional profile of the gut microbiota influences the effectiveness of probiotic treatment in patients with schizophrenia. A total of 29 patients with schizophrenia consumed Bifidobacterium breve A-1 (synonym B. breve MCC1274) for 4 weeks. We considered patients who showed a 25% or more reduction in the Hospital Anxiety and Depression Scale total score at 4 weeks from baseline to be “responders” and those who did not to be “non-responders”. We predicted the gut microbial functional genes based on 16S rRNA gene sequences and applied the linear discriminant analysis effect size method to determine the gut microbial functional genes most likely to explain the differences between responders and non-responders at baseline. The results showed that lipid and energy metabolism was elevated at baseline in responders (n = 12) compared to non-responders (n = 17). These findings highlight the importance of assessing the gut microbial functional genes at baseline before probiotic therapy initiation in patients with psychiatric disorders.

Do gut microbiota associate with the ovulatory cycle in women showing normogonadotrophic anovulation? In humans, the gut microbiota affects diverse physiological functions and dysbiosis (microbial imbalance) may lead to pathological syndromes. However, there is comparatively little information on the relevance of gut microbiota to reproductive functions in women. Here, a group of women with idiopathic chronic anovulation were examined, who do not exhibit any apparent endocrinological disorder, as they are suitable for investigating the relationship between intestinal bacteria and ovulatory disorders. A prospective observational cohort study was performed on two groups of women who did not exhibit apparent endocrinological disorders but showed either irregular menstrual cycles (IMC group) or normal menstrual cycles (controls). The bacterial composition of faeces from rectal swabs from the women was analysed using next-generation sequencing based on bacterial 16SrRNA genes. A metagenomic analysis indicated that the two groups of women had significant differences in 28 bacterial taxa in their faeces. Prevotella-enriched microbiomes were more abundant in the IMC group, whereas Clostridiales, Ruminococcus and Lachnospiraceae (butyrate-producing bacteria) were present at lower levels in the IMC group. Distinctive subpopulations of intestinal microbiota were identified in women with unexplained chronic anovulation. The results indicate that gut microbiota could be associated with ovarian functions.

Background/Objectives: Sarcopenia (SA), an age-related impairment in skeletal muscle mass and function, is related to gut microbiota (GM) through inflammation and short-chain fatty acid (SCFA) generation. However, data on this relationship in older Japanese adults remain limited. We investigated the relationship of GM composition with SA, based on the Asian Working Group for Sarcopenia (AWGS) 2019 criteria, among elderly Japanese outpatients. Methods: Between June 2022 and January 2023, this prospective cross-sectional study enrolled 356 community-dwelling outpatients aged ≥ 65 years at the Department of Gastroenterology, Juntendo Tokyo Koto Geriatric Medical Center. SA was determined based on the AWGS 2019 consensus criteria. GM was analyzed using 16S rRNA gene sequencing, and alpha/beta diversity, taxonomic composition, detection rates, and correlations with skeletal muscle mass index (SMI), grip strength, and gait speed were investigated. Results: Among 356 (144 males, 212 females) participants, 50 (35 males, 15 females) had SA. Differences in GM diversity and composition were primarily noted among male participants. Men with SA had lower alpha diversity and distinct beta diversity profiles. Six bacterial genera—Eubacterium I, Fusicatenibacter, Holdemanella, Unclassified Lachnospira, Enterococcus H, and Bariatricus—had lower abundances in the SA group. Several of these genera showed positive correlations with SMI, grip strength, and gait speed. Conversely, no differences in GM characteristics were seen among females. Conclusions: GM composition was associated with SA among older Japanese men. These sex-specific differences emerged consistently, highlighting the potential of microbiota-based strategies for SA prevention in older males.

Background: Oral probiotic intake is suggested to have positive effects on skin. We aimed to elucidate the effects of oral Bifidobacterium breve M-16V intake on skin by analyzing facial images, the skin myco/microbiota, and the gut microbiota. Methods: We conducted a randomized, double-blind, placebo-controlled study in Japan. Healthy women aged over 30 years were randomly allocated to either the B. breve (1 × 1010 colony-forming units (CFU)/sachet, two sachets daily) or the placebo group and consumed the corresponding study food for 12 weeks. Facial images were taken at weeks 0, 4, 8, and 12 using VISIA evolution. Stool and skin samples were collected at weeks 0 and 12. The primary outcome was the change in the total VISIA score from baseline. Results: A total of 120 females aged 30–79 years were assigned to the B. breve (n = 59) or placebo (n = 61) group. The total VISIA score worsened in the placebo group at week 8 (p = 0.029) but not in the B. breve group. Compared with that of the placebo group, the VISIA brown spot score of the B. breve group improved at weeks 4 (p = 0.013) and 8 (p = 0.041). The VISIA pore score improved at weeks 4 (p = 0.013), 8 (p = 0.041), and 12 (p = 0.004) within the B. breve group. Genus-level analysis of the gut microbiota revealed a significant increase in Blautia abundance in the B. breve group. The frequency of adverse events was not different between the groups. Conclusions: Oral B. breve M-16V administration may suppress skin deterioration, including the appearance of brown spots, on the faces of adult females.